1. Field of the Invention
The invention relates to a refueling device for refueling a fuel tank of an internal combustion engine. The invention also relates to a motor vehicle having such a refueling device. The invention can be applied to any vehicle, but will be explained in detail with reference to a passenger car
2. Description of the Related Art
A motor vehicle typically has a fuel container to carry fuel to operate an internal combustion engine. A refueling device is arranged on and connected to the fuel tank and functions to fill the fuel tank with fuel. The fuel is fed to the internal combustion engine of the motor vehicle via a fuel line. A venting device usually is provided on the fuel tank to vent the fuel tank if an excessively high gas pressure occurs therein. The gas pressure rises, for example, when the volatile components of the fuel go into the gas phase. This venting device often is equipped with a pressure holding valve that opens at a specific gas pressure and closes again automatically at a specific gas pressure. The venting device also has a filter, such as an activated carbon filter, for cleaning the exhaust air that is discharged from the fuel tank. The filter device and the pressure holding valve cause the venting device to have certain flow resistance, which makes reliable reduction of pressure in the fuel tank more difficult. This is disadvantageous during a refueling process since fuel can accumulate in a filler connector of the fuel tank.
DE 10 2004 011 119 A1 describes a fuel tank with a venting device with an equalization volume. The venting device is in the interior of the fuel tank and has at least two venting points for discharging fuel vapors. The venting points each connect to a venting section and have a venting opening. A pressure holding valve with a predefined opening pressure is downstream of the venting opening. The venting point of the first venting point is geodetically higher and the associated pressure holding valve has a larger opening pressure value than the opening pressure value of the pressure holding valves of the further venting points. The further venting points have a float valve upstream of their pressure holding valve, but the first venting point has not float valve. However, this arrangement has proven to be disadvantageous, if the internal pressure in the fuel tank is not reduced quickly enough due to the large resistance of the venting device. Fuel nevertheless can accumulate in the filler connector, and hence a fuel nozzle located in the filler connector switches off and a refueling process therefore is interrupted.
The invention is based on the object of making available an improved refueling device which overcomes the abovementioned disadvantages.